Furnace.



PATENTED OCT. 11, 1904.

S. F. PIERCE.

FURNACE. APPLIGATION FILED MAY 27, 1904.

no MODEL.

UNITED STATES Patented October 11, 1904.

PATENT OFFICE.

FURNACE.

SPECIFICATION forming part of Letters Patent No 772,053, dated October 11, 1904.

Application filed May 2'7, 1904:. Serial No. 210,017. (No model.) i

To a whom, it may concern:

Be it known that I, SIMEoN F. PIERCE, acitizen of the United States, residing at St. Paul, in the county of Ramsey and State of Minnesota, have invented certain new and useful Improvements in Furnaces, of which the following is a specification.

My invention relates to improvements in furnaces having brick or masonry settings, its object being to provide improved means for supplying highly-heated air to the interior of the fire-box and distributing it therein in such way as efiiciently to consume the smoke and gaseous products of combustion.

In order to effect perfect combustion and completely to consume the smoke and gases without cooling the fire, it is important that the air to be introduced be first heated to as nearly as possible the temperature of the fire and then distributed over the entire grate-surface and throughout the fire-boxand held in the fire-box long enough to burn up the smoke and gases.

To that end my invention consists in the features of construction, combination, and arrangement of parts hereinafter described and claimed.

In the accompanying drawings, forming part of this specification, Figure 1 is a horizontal section of a steam-boiler furnace embodying my invention, taken above the top of the bridge-wall and looking down; and Fig. 2 is a vertical section on line a: w of Fig. 1.

In the drawings, A represents the front wall, B B the side walls, and C the bridge-wall, of the furnace.

D represents the grate, E the fire-box between the walls B, and F the crown-sheet of the boiler. (Shown in Fig. 2 partly broken away.)

Leading from the outside of the furnace through the side or front walls are a number of pipes 2, 3, and 4, arranged along the inside of the side walls and preferably the front of the bridge-wall, so that they will be directly exposed to the fire and will lie between the fire and the furnace-walls. Of these pipes some or all, such as those numbered 2 in the drawings, may be led along on the front side of the bridge'wall, others may be arranged to extend above and rest upon the top of the bridge-wall, like those numbered 3, while others yet may be led through the interior of the bridge-wall, such as those numbered 4. The pipes are of such length and so disposed as to discharge into the fire-box at any selected points. In order that the air may be discharged as far into the interior of the fire-box as possible, the pipes are provided with inturned ends or nozzles 5, projecting inwardly toward'the interior of the fire-box. This arrangement serves to-prevent the entering air from being carried offovervthe bridge-wall before it has thoroughly commingled with the smoke and gases. In order that the entering air may be thoroughly and evenly distributed over the surface of the grate and throughout the interior of the fire-box, the discharge-nozzles are not only arranged at differentheights and at frequent intervals along the side walls and bridge-wall, but are projected for the most part obliquely across the grate, so as to impart to the smoke, gases, and air in the firebox a swirling or rotary motion, as indicated by the arrows in Fig. 1, which will delay the passage of the air over the bridge-wall until it has had time thoroughly to commingle with the smoke and gases and consume them. Thus by referring to the drawings it will be seen that all of the discharge-nozzles along the bridge-wall are directed toward the same side a wall and approximately in the same direction and the nozzles shown upon the side walls are directed, respectively, toward thefront wall and bridge-wall.

I By making the pipes of metal and leading them around inside the fire-box the contained air becomes intensely heated, and its expansion is so great as to create a strong blast at the point of discharge. This not only enables a large amount of air to be introduced into the fire-box, but causes it to be discharged with such force that it is projected into the interior of the box, where it can mingle with the products of combustion before passing over the bridge-wall. Furthermore, by arranging these pipes along the inside of the furnace-walls the walls are kept comparatively cool and are saved from the destructive action of the heat of a fire in juxtaposition with them. It will be noticed that each pipe leads independently to the outside air, so that the amount of air that will be discharged through any one nozzle may be fixed and controlled. carried through the side walls; but, if desired, they may be introduced through the front wall, as indicated in dotted lines in Fig. 1. It may also be desirable in order to secure greater heating-surface to double some of the pipes back upon themselves along the side wall without carrying them along the bridgewall, as shown in the drawings in the case of the pipe marked 6.

I am aware that furnaces have been constructed with air-passages in the interior of the walls communicating with the fire-box through openings in the wall; but such passages and openings do not accomplish the results attained by my invention.-

It is obvious that various modifications may be made in the details of the construction without departing from the principle of the invention, the scope of which is defined in the claims.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a furnace, the combination, with the fire-box and its walls, of metallic pipes arranged along the inner side of one of said walls, each pipe leading separately from the outside air and discharging into the fire-box at a single predetermined point. 1

2. In a furnace, the combination, with the firebox and its walls, of metallic pipes arranged along the inner side of one of said walls, each pipe leading separately from the outside air and having a single discharge-noz- In the drawings the pipes are shown zle projecting inwardly into the fire-box at a predetermined point.

3. In a furnace, the combination, with the fire-box and its side and bridge walls, of metallic pipes arranged along the inner side of one of said walls, and having their discharge ends along the bridge-Wall, each pipe leading separately from the outside air and discharging into the fire-box at a single predetermined point.

4. In a furnace of the class described, the combination, with the fire-box and its side and bridge walls, of air-pipes arranged along the inner side of the side wall and on the front side of the bridge-wall, said pipes having their discharge ends along the bridge-wall and being provided with nozzles extending inwardly from the bridge-wall, whereby the air is discharged into the interior of the firebox.

5. In a furnace, the combination, with the fire-box and its side and bridge walls, of metallic pipes arranged along the inner side of one of said walls and having their dischargeends along the bridge-wall, the discharge ends being provided with nozzles extending inwardly from the bridge-wall, whereby the air is discharged into the interior of the fire-box.

6. In a furnace, the combination, with the fire-box and bridge-wall, of metallic pipes ex tending along the top of the bridge-wall, each pipe leading separately from the outside air and having a single dischargenozzle directed inwardly from the top of the bridge-wall at a predetermined point.

In testimony whereof I affix my signature in presence of two witnesses.

SIMEON F. PIERCE.

Witnesses:

ARTHUR P. .LOTHROP, EMILY F. OTIS. 

